Vent with relief valve

ABSTRACT

A vent assembly has a housing defining a cavity, a first end, a second end, a vent opening, a valve opening, and a coupling structure towards the second end. The housing defines a valve opening and a vent opening. A vent is coupled to the housing across the vent opening, and a one-way relief valve is sealably disposed on the housing across a valve opening.

RELATED APPLICATIONS

This is a continuation application of U.S. patent application Ser. No.17/359,147, filed Jun. 25, 2021, which is a continuation application ofU.S. patent application Ser. No. 16/497,596, filed Sep. 25, 2019, issuedas U.S. Pat. No. 11,047,508 on Jun. 29, 2021, which is a § 371 U.S.National Stage of International Application No. PCT/US2018/025346, filedMar. 30, 2018, which claims the benefit of U.S. Provisional ApplicationSer. No. 62/478,872, filed Mar. 30, 2017, the disclosures of each ofwhich are incorporated herein by reference in their entireties.

TECHNOLOGICAL FIELD

The current technology generally relates to a vent. More particularlythe current technology relates to a vent with integrated relief valvefunctionality.

BACKGROUND

Protective vents are typically employed to allow pressure equalizationbetween a casing and the environment outside of the casing. Vents canuse a water, dust, and oil resistant membrane to allow gas pressures toequalize while preventing liquid and solid contaminants to pass through.However, in some technological areas, it is possible for the pressureinside of the casing to spike drastically, and the protective vent isinsufficient to achieve equilibrium quickly enough to prevent damage tocomponents in the casing, or the casing itself. For example, in abattery casing having multiple cells, if a single cell explodes, theresulting pressure in the battery casing can cause damage to the othercells in the casing, or cause the casing to burst under the highpressure

SUMMARY

The technology disclosed herein relates to a vent having a relief valve.In some examples, the vent is configured to passively allow gas to ventbetween a casing and the outside environment under normal operatingconditions. However, upon a pressure spike inside the casing, a reliefvalve allows gas to bypass the vent. In some example implementations thetechnology disclosed herein is employed on the casing of a battery.

BRIEF DESCRIPTION OF THE DRAWINGS

The present technology may be more completely understood and appreciatedin consideration of the following detailed description of variousembodiments in connection with the accompanying drawings.

FIG. 1 is an example vent having a relief valve consistent withimplementations of the technology disclosed herein.

FIG. 2 is the example vent of FIG. 1 .

FIG. 3 is another example vent having a relief valve consistent withimplementations of the technology disclosed herein.

FIG. 4 is the example vent of FIG. 3 .

FIG. 5 is another example vent having a relief valve consistent withimplementations of the technology disclosed herein.

FIG. 6 is the example vent of FIG. 5 .

FIG. 7 is another example vent having a relief valve consistent withimplementations of the technology disclosed herein.

FIG. 8 is a perspective cross-sectional view of the vent of FIG. 7 .

FIG. 9 is a facing view of the cross-section depicted in FIG. 8 .

FIG. 10 is an exploded perspective view of an example vent having arelief valve consistent with some implementations of the technologydisclosed herein.

FIG. 11 is an exploded perspective view of yet another example venthaving a relief valve consistent with some implementations of thetechnology disclosed herein.

DETAILED DESCRIPTION

In a variety of embodiments, the present technology combines thefunction of a protective vent with the functionality of a 1-way reliefvalve. The vent allows for venting of an enclosure during normaloperation conditions, but if there is a high-pressure event in theenclosure, such as an explosive release of gas or a relatively largetemperature increase in a relatively short period of time, the assemblycan open to allow higher unrestricted airflow to avoid overpressure inthe enclosure that could otherwise cause damage to internal componentsof the enclosure.

FIG. 1 is an example assembly 10 having a vent and relief valveconsistent with implementations of the technology disclosed herein. FIG.2 is the assembly 10 of FIG. 1 in an alternate state. The assembly 10 isgenerally configured to couple to a casing 40 and accommodate gas flowin to and out of the casing 40 from the ambient environment under normaloperation. Upon a high-pressure event inside the casing 40, the assembly10 is configured to allow gas to escape the casing 40 relatively quicklyby bypassing the assembly 10.

The assembly 10 has a vent 20 and a coupling structure 30. The vent 20is generally positioned in fluid communication with an opening 42 in thecasing 40. The vent 20 is configured to allow gases to pass into and outof the casing 40 from the environment outside of the casing 40, byflowing through vent 20. In some embodiments, the vent 20 is configuredto prevent particles from entering into the casing 40. In someembodiments, the vent 20 is also configured to prevent liquids fromentering into the casing 40. The vent 20 can be constructed of a varietyof different materials and combinations of materials. In variousembodiments the vent 20 incorporates a breathable membrane, such aspolytetrafluroethylene (PTFE) or other types of breathable membranes.The vent 20 can be a laminate or composite that includes a breathablemembrane, such as a PTFE laminated to a woven or non-woven supportlayer. In some embodiments, the vent 20 is a woven fabric or a non-wovenfabric. The vent 20 can be constructed of hydrophobic material, or thevent 20 can be treated to exhibit hydrophobic properties. In oneexample, the vent 20 is a hydrophobic woven or non-woven fabric. In someembodiments the vent 20 has a support ring to support the periphery ofthe venting material.

The coupling structure 30 is configured to couple the vent 20 to thecasing 40 under normal pressure conditions. When the pressure inside thecasing 40 spikes above a threshold T, the coupling structure 30 releasesto allow gas escaping from the casing 40 to bypass vent 20, as depictedin FIG. 2 . The coupling structure 30 is generally an adhesive. Thecoupling structure 30 can be a pressure-sensitive adhesive. In someembodiments the coupling structure 30 is a double-sided adhesive tape.

The casing 40 is generally configured to encase components. In oneexample, the casing 40 is a housing for battery cells, in anotherexample, the casing 40 is for other types of systems.

FIG. 3 is another example vent having a relief valve consistent withimplementations of the technology disclosed herein. FIG. 4 is theexample vent of FIG. 3 with the relief vent in an alternate position.The assembly 100 is generally configured to couple to a casing 140 andaccommodate gas flow in to and out of the casing 140 from the ambientenvironment under normal operation. Upon a high-pressure event insidethe casing 140, the assembly 100 is configured to allow gas to escapethe casing 140 relatively quickly by bypassing the assembly 100. Theassembly 100 has a vent housing 110, a spring 120, and a vent 130.

The vent 130 and casing 140 are generally consistent with that describedabove in the discussion of FIG. 1 . The vent housing 110 is generallyconfigured to couple to the casing 140. In some embodiments the venthousing 110 has a coupling surface 114 that is configured to be coupledto the casing 140. The coupling surface 114 can be coupled to the casing140 with an adhesive, in some embodiments. In other embodiments thecoupling surface 114 can define a mating structure that is configured tomate with a corresponding structure defined by the casing 140. In someembodiments the coupling surface 114 of the vent housing 110 is weldedto the casing 140. The vent housing 110 can be constructed of a varietyof different materials and combinations of materials. In someembodiments the vent housing 110 is a molded plastic. In anotherembodiment the vent housing 110 is a metal.

The vent housing 110 is generally configured to position the vent 130over an opening 142 defined by the casing 140. The vent housing 110 isfixed to a first end 122 of the spring 120 and the vent 130 is fixed toa second end 124 of the spring 120. The spring 120 is biased in a stateof compression between the vent housing 110 and the casing 140 such thatthe spring 120 couples the vent 130 to the casing 140 about the opening142 under normal pressure conditions. When the pressure inside thecasing 140 spikes above a threshold T, the pressure is exerted on asecond side 134 of the vent 130 against the pressure exerted on a firstside 132 of the vent by the spring 120, which can translate at least aportion of the vent 130 away from the surface of the casing 140 tocompress at least a portion of the spring 120. Pressurized gas frominside the casing 140 is allowed to escape the casing 140 and bypass thevent 130. In some embodiments, once the pressure inside the casing 140returns to the threshold T or below, the spring 120 returns the vent 130to position over the opening 142 in the casing 140.

The spring 120 can be a helical coil constructed of metal or plastic, insome embodiments. In some embodiments, the spring 120 can be a resilientmaterial such as a foam material. The spring 120 can also be multiplecoils, in some embodiments.

In some, but not all embodiments, the vent housing 110 can define anairflow pathway 112 that facilitates the passage of released gas fromthe casing 140 that bypasses the vent 130.

FIG. 5 is another example vent having a relief valve consistent withimplementations of the technology disclosed herein. FIG. 6 is theexample vent of FIG. 5 upon a high-pressure event inside a casing 240.The assembly 200 is similar to assemblies previously described, wheregas is allowed to pass between the casing 240 and the environmentthrough a vent 230 under normal pressure conditions. Upon high pressureinside the casing 240, the assembly 200 allows gases from inside thecasing 240 to bypass the vent 230.

The assembly 200 generally has a coupling structure 210, a spring 220, ahinge 222, and the vent 230. The vent 230 is positioned in fluidcommunication with an opening 242 defined in the casing 240. The casing240 and the vent 230 are consistent with those already described hereinabove.

The coupling structure 210 is generally configured to couple theassembly 200 to the casing 240. The coupling structure 210 can beconfigured, for example, to receive an adhesive that couples to thecasing 240. In some embodiments the coupling structure 210 definesmating features that are configured to mate with corresponding featuresdefined by the casing 240. In some embodiments the coupling structure210 is coupled to the casing 240 through welding. Other approaches tocoupling the coupling structure 210 to the casing 240 can certainly beused, as well.

The hinge 222 couples the vent 230 to the coupling structure 210. Thespring 220 pushes against a first side 232 of the vent to bias the vent230 against the casing 240 about the opening 242 under normal pressureconditions. When pressure inside the casing 240 spikes above a thresholdT, the gas in the casing 240 pushes against a second side 234 of thevent 230 against the spring 220, which translates the vent 230 away fromthe casing 240 and causes the spring 220 to compress. An opening is thendefined between the vent 230 and the casing 240 (FIG. 6 ), which allowsthe gas inside the casing 240 to escape from the casing 240 and bypassthe vent 230. The hinge defines the translation path of the vent 230,which is a pivot. In various embodiments, when the pressure inside thecasing 240 returned to the threshold T or below, the spring 220 isconfigured to translate the vent 230 about the hinge 222 to its initialposition (FIG. 5 ) against the casing 240 about the opening 242.

The spring 220 can be consistent with springs described above in thediscussion of FIGS. 3-4 . The hinge 222 can have a variety ofconfigurations and generally defines a pivot axis of the vent 230relative to the casing 240.

FIG. 7 is a perspective view of an example vent having a relief valveconsistent with implementations of the technology disclosed herein. FIG.8 is a cross-sectional view of the vent of FIG. 7 and a casing 370, andFIG. 9 is a perspective view of the cross-section of FIG. 8 . Similar toassemblies previously described, the current assembly 300 is generallyconfigured to allow gases to pass between a casing 370 and theenvironment through a vent 330 under normal pressure conditions. Upon ahigh-pressure event inside the casing 370, the assembly 300 isconfigured to allow gases to escape the casing 370 by bypassing the vent330. The assembly 300 generally has a vent housing 320, a couplingstructure 310 a mounting surface 350, a vent 330, and a relief valve340.

The vent housing 320 is generally configured to house the vent 330 andthe relief valve 340. The vent housing 320 defines a cavity 322, a firstend 302, a second end 304, and a coupling structure 310. The venthousing 320 can be constructed of a variety of materials andcombinations of materials. In some embodiments the vent housing 320 isconstructed of plastic or metal. In one example, at least a portion ofthe vent housing 320 is an injection-molded plastic. An end cap 324 iscoupled to the vent housing 320 towards the first end 302. The end cap324 can form a unitary component with the vent housing 320 in some otherembodiments. The cavity 322 is also defined by the end cap 324.

The mounting surface 350 is generally positioned between the first end302 and the second end 304 within the cavity 322. The mounting surface350 is generally configured to receive the vent 330 and the relief valve340. While the mounting surface 350 can be a single planar surface, insome other embodiments the mounting surface can be defined by multiplesurfaces that are not necessarily planar. The mounting surface 350defines a vent opening 352 and a valve opening 354. The vent opening 352and the valve opening 354 can each be one or more openings defined bythe mounting surface 350. In a variety of embodiments, the mountingsurface 350 is a unitary structure with the vent housing 320. In someother embodiments, however, the mounting surface 350 is defined by aseparate component that is coupled to the vent housing 320, eitherthrough a frictional fit or through the use of couplers such as screws.

The vent 330 is coupled to the mounting surface 350 across the ventopening 352. The vent 330 is generally configured to allow passiveairflow between the casing 370 and the ambient environment whilepreventing liquids and particulates from entering into the casing 370.The vent 330 is positioned in fluid communication with the opening 372in the casing 370. The vent 330 can be coupled to the mounting surface350 with an adhesive. The vent 330 can be constructed of materialssimilar to vents described herein above. In the current example, thevent 330 forms an annulus, and the vent 330 can be coupled to themounting surface 350 with adhesive disposed adjacent to its outerperimeter 332 and its inner perimeter 334 to form a seal between thevent 330 and the mounting surface 350.

The valve 340 is sealably disposed on the mounting surface 350 acrossthe valve opening 354. In a variety of embodiments, the valve 340 is anumbrella valve. The valve 340 is generally configured to form a sealaround the valve opening 354 to allow gases to passively vent throughthe vent opening 352 and vent 330 under normal pressure conditions and,upon a pressure spike within the casing 370 above a threshold T, thepressure displaces the umbrella valve 340 to unseal from the valveopening 354 and allow gas to bypass the vent 330 and exit the casing 370through the valve opening 354. The valve 340 is configured in parallelwith the vent 330 with respect to airflow between the ambientenvironment and the casing 370.

The relief valve 340 is generally formed of an elastomeric material. Therelief valve 340 can also be other types of relief valves, but willgenerally be a one-way relief valve. The relief valve 340 can be anytype of umbrella valve, such as a Belleville valve. In some embodimentsthe relief valve 340 is configured to reseal around the valve openings354 when the pressure inside the casing 370 returns to a level at orbelow the pressure threshold T.

The coupling structure 310 is generally configured to couple theassembly 300 to a casing 370 (FIG. 8 ) about an opening 372 defined bythe casing 370. The coupling structure 310 is defined towards the secondend 304 of the vent housing 320. The coupling structure 310 is generallyconfigured to engage the casing 370. In the current example, thecoupling structure 310 forms a snap-fit connection with the casing 370.In some other embodiments, the coupling structure 310 forms a matingstructure that is configured to mate with a corresponding structuredefined by the casing 370. For example, the coupling structure 310 candefine a screw thread configured to be received by the casing 370 aboutthe opening 372. As another example, the coupling structure 310 candefine a connector that interlocks with the casing 370 about the opening372, such as a bayonet connector. In some embodiments, the couplingstructure 310 can be coupled to the casing 370 about the opening 372with an adhesive.

In embodiments consistent with the current example, a seal 312 generallyabuts the coupling structure 310. The seal 312 is configured to create aseal between the assembly 300 and the casing 370 when the assembly 300is coupled to the casing 370. The seal 312 can be an elastomericmaterial. In some embodiments the seal 312 is rubber or anothergasketing or sealing material.

In examples consistent with the current embodiment, the vent housing 320defines an opening 326 between the ambient environment and the cavity322 to define a first fluid flow pathway between the outside of the venthousing 320 and the mounting surface 350 and/or the vent 330. Also, thecoupling structure 310 defines a second fluid flow pathway between theoutside of the vent housing 320 and the vent 330. In such embodiments,the umbrella valve 340 is configured to unseal from the mounting surface350 when the pressure in the second fluid flow pathway is greater thanthe pressure in the first fluid flow pathway by at least 0.2 psi and nomore than 3 psi and, in some embodiments, from 0.5 psi to 1 psi.

The vent housing 320 has an obstruction 358 positioned between theopening 326 and the vent 330. The obstruction 358 creates a tortuouspath between the opening 326 and the vent 330, meaning that fluidflowing into the opening 326 cannot directly impact the vent 330.Similarly, the obstruction 358 is positioned between the opening 326 andthe valve 340.

In examples consistent with the current embodiment, the vent 330 and thevalve 340 are concentric. While the valve 340 is central to the vent330, in some other embodiments the vent can be central to the valve. Inexamples consistent with the current embodiment, the vent housing 320defines a central axis X extending from the first end 302 to the secondend 304. The mounting surface 350 is about the central axis x. Althoughnot completely visible in the current views, the valve opening 354 is aplurality of openings defining a segmented annulus about the centralaxis X. Similarly, the vent opening 352 is a plurality of openingsdefining a segmented annulus about the central axis X. Furthermore, themounting surface defines a central opening 356 about the central axis Xand the umbrella valve 340 has an extension portion 342 that extendsthrough the central opening 356. The opening 326 defined by the venthousing 320 are a series of radial openings about the central axis X.

FIG. 10 is an exploded view of another example assembly 400 with a vent430 and a relief valve 440 consistent with some implementations of thetechnology disclosed herein. Similar to assemblies previously described,the current assembly 400 is generally configured to allow gases to passbetween a casing (not currently depicted) and an outside environmentthrough a vent 430 under normal pressure conditions. Upon ahigh-pressure event inside the casing, the assembly 400 is configured toallow gases to escape the casing by bypassing the vent 430. The assembly400 generally has a vent housing 420, a mounting surface 450, a vent430, and a relief valve 440.

The vent housing 420 is generally configured to house the vent 430 andthe relief valve 440. The vent housing 420 defines a cavity 422, a firstend 402, a second end 404, and a coupling structure 410. The venthousing 420 can be constructed of a variety of materials andcombinations of materials, as discussed above. An end cap 424 is coupledto the vent housing 420 towards the first end 402. The end cap 424 canform a unitary component with the vent housing 420 in some otherembodiments. The cavity 422 is also defined by the end cap 424.

The mounting surface 450 is generally positioned between the first end402 and the second end 404 within the cavity 422. The mounting surface450 is generally configured to receive the vent 430 and the relief valve440. The mounting surface 450 defines a vent opening 452 and a valveopening 454. The vent opening 452 and the valve opening 454 can each beone or more openings defined by the mounting surface 450. The mountingsurface 450 can be configured as discussed herein above. In the currentexample, the vent opening 452 is a single circular opening, and thevalve opening 454 is a series of circular openings surrounding a valveextension opening 456 that is central to the valve openings.

The vent 430 is coupled to the mounting surface 450 across the ventopening 452. The vent 430 is generally configured to allow passiveairflow between the casing and the ambient environment while preventingliquids and particulates from entering into the casing. The vent 430 ispositioned in fluid communication with the opening in the casing. Thevent 430 can be coupled to the mounting surface 450 with an adhesive.The vent 430 can be constructed of materials similar to vents describedherein above. In the current example, the vent 430 is circular, and thevent 430 can be coupled to the mounting surface 450 with adhesivedisposed adjacent to its outer perimeter 432 to form a seal between thevent 430 and the mounting surface 450.

The valve 440 is sealably disposed on the mounting surface 450 acrossthe valve openings 454. In a variety of embodiments, the valve 440 is anumbrella valve. The valve 440 has an extension portion 442 that isreceived by the central valve extension opening 456. The valve 440 isgenerally configured to form a seal around the valve opening 454 toallow gases to passively vent through the vent opening 452 and vent 430under normal pressure conditions and, upon a pressure spike within thecasing above a threshold T, the pressure displaces the umbrella valve440 to unseal from the valve opening 454 and allow gas to bypass thevent 430 and exit the casing through the valve opening 454. The valve440 is configured in parallel with the vent 430 with respect to airflowbetween the ambient environment and the casing.

The relief valve 440 is generally formed of an elastomeric material. Therelief valve 440 can also be other types of relief valves, but willgenerally be a one-way relief valve. The relief valve 440 can be anytype of umbrella valve, such as a Belleville valve. In some embodimentsthe relief valve 440 is configured to reseal around the valve openings454 when the pressure inside the casing returns to a level at or belowthe pressure threshold T.

The coupling structure 410 is generally configured to couple theassembly 400 to a casing about an opening defined by the casing. Thecoupling structure 410 is defined towards the second end 404 of the venthousing 420. The coupling structure 410 is generally configured toengage the casing. In the current example, the coupling structure 410 isa bottom (relative to the figure) surface that can be coupled to thecasing about the opening with an adhesive. Alternate types of couplingstructures 410 can also be used, as described above.

In examples consistent with the current embodiment, the vent housing 420defines an opening 426 between the ambient environment and the cavity422 to define a first fluid flow pathway between the outside of the venthousing 420 and the mounting surface 450 and/or the vent 430. Also, thecoupling structure 410 defines a second fluid flow pathway between theoutside of the vent housing 420 and the vent 430. In such embodiments,the umbrella valve 440 is configured to unseal from the mounting surface450 when the pressure in the second fluid flow pathway is greater thanthe pressure in the first fluid flow pathway by at least 0.2 psi and nomore than 2 psi and, in some embodiments, from 0.5 psi to 1 psi.

The vent housing 420 has an obstruction 458 positioned between theopening 426 and the vent 430. The first obstruction 458 creates atortuous path between the opening 426 and the vent 430, meaning thatfluid flowing into the opening 426 cannot directly impact the vent 430.Similarly, one or more second obstructions 459 are positioned betweenthe opening(s) 426 and the valve 440. The second obstruction(s) 459creates a tortuous path between the opening 426 and the valve, meaningthat fluid flowing into the opening 426 cannot directly impact the valve440.

FIG. 11 is an exploded view of another example assembly 500 with a vent530 and a relief valve 540 consistent with some implementations of thetechnology disclosed herein. Similar to assemblies previously described,the current assembly 500 is generally configured to allow gases to passbetween a casing (not currently depicted) and an outside environmentthrough a vent 530 under normal pressure conditions. Upon ahigh-pressure event inside the casing, the assembly 500 is configured toallow gases to escape the casing by bypassing the vent 530. The assembly500 generally has a vent housing 520, a mounting surface 550, a vent530, and a relief valve 540.

The vent housing 520 is generally configured to house the vent 530 andthe relief valve 540. The vent housing 520 defines a cavity 522, a firstend 502, a second end 504, and a coupling structure 510. The venthousing 520 can be constructed of a variety of materials andcombinations of materials, as discussed above. An end cap 524 is coupledto the vent housing 520 towards the first end 502. The end cap 524 canform a unitary component with the vent housing 520 in some otherembodiments. The cavity 522 is also defined by the end cap 524.

The mounting surface 550 is generally positioned between the first end502 and the second end 504 within the cavity 522. The mounting surface550 is generally configured to receive the vent 530 and the relief valve540. The mounting surface 550 defines a vent opening 552 and a valveopening 554. The vent opening 552 and the valve opening 554 can each beone or more openings defined by the mounting surface 550. The mountingsurface 550 can be configured as discussed herein above, and in thecurrent example the mounting surface 550 has two surfaces. In thecurrent example, the vent opening 552 is a single circular opening, andthe valve opening 554 is a series of circular openings surrounding avalve extension opening 556 that is central to the valve openings 554.

The vent 530 is coupled to the mounting surface 550 across the ventopening 552. The vent 530 is generally configured to allow passiveairflow between the casing and the ambient environment while preventingliquids and particulates from entering into the casing. The vent 530 ispositioned in fluid communication with the opening in the casing. Thevent 530 can be coupled to the mounting surface 550 with an adhesive.The vent 530 can be constructed of materials similar to vents describedherein above. In the current example, the vent 530 is circular, and thevent 530 can be coupled to the mounting surface 550 with adhesivedisposed adjacent to its outer perimeter 532 to form a seal between thevent 530 and the mounting surface 550.

The valve 540 is sealably disposed on the mounting surface 550 acrossthe valve openings 554. In a variety of embodiments, the valve 540 is anumbrella valve. The valve 540 has an extension portion 542 that isreceived by the central valve extension opening 556. The valve 540 isgenerally configured to form a seal around the valve opening 554 toallow gases to passively vent through the vent opening 552 and vent 530under normal pressure conditions and, upon a pressure spike within thecasing above a threshold T, the pressure displaces the umbrella valve540 to unseal from the valve opening 554 and allow gas to bypass thevent 530 and exit the casing through the valve opening 554. The valve540 is configured in parallel with the vent 530 with respect to airflowbetween the ambient environment and the casing.

The relief valve 540 is generally formed of an elastomeric material. Therelief valve 540 can also be other types of relief valves, but willgenerally be a one-way relief valve. The relief valve 540 can be anytype of umbrella valve, such as a Belleville valve. In some embodimentsthe relief valve 540 is configured to reseal around the valve openings554 when the pressure inside the casing returns to a level at or belowthe pressure threshold T.

The coupling structure 510 is generally configured to couple theassembly 500 to a casing about an opening defined by the casing. Thecoupling structure 510 is defined towards the second end 504 of the venthousing 520. The coupling structure 510 is generally configured toengage the casing. In the current example, the coupling structure 510 isthe bottom (relative to the figure) surface that can be coupled to acasing about an opening with an adhesive. Alternate types of couplingstructures 510 can also be used, as described above.

It is noted that, in embodiments consistent with the current example,the cavity 522 is actually two separate cavities, one that houses thevalve 540, and the other than houses the vent 530. In some embodimentsthere is a single cavity. In examples consistent with the currentembodiment, the vent housing 520 defines an opening 526 between theambient environment and the cavity 522 to define a first fluid flowpathway between the outside of the vent housing 520 and the mountingsurface 550 and/or the vent 530. Also, the coupling structure 510defines a second fluid flow pathway between the outside of the venthousing 520 and the vent 530. In such embodiments, the umbrella valve540 is configured to unseal from the mounting surface 550 when thepressure in the second fluid flow pathway is greater than the pressurein the first fluid flow pathway by at least 0.2 psi and no more than 2psi and, in some embodiments, from 0.5 psi to 1 psi.

The vent housing 520 has an obstruction 558 positioned between theopening 526 and the vent 530. The first obstruction 558 creates atortuous path between the opening 526 and the vent 530, meaning thatfluid flowing into the opening 526 cannot directly impact the vent 530.Similarly, one or more second obstructions 559 are positioned betweenthe opening(s) 526 and the valve 540. The second obstruction(s) 559creates a tortuous path between the opening 526 and the valve, meaningthat fluid flowing into the opening 526 cannot directly impact the valve540.

It should also be noted that, as used in this specification and theappended claims, the phrase “configured” describes a system, apparatus,or other structure that is constructed or configured to perform aparticular task or adopt a particular configuration. The phrase“configured” can be used interchangeably with other similar phrases suchas “arranged”, “arranged and configured”, “constructed and arranged”,“constructed”, “manufactured and arranged”, and the like.

All publications and patent applications in this specification areindicative of the level of ordinary skill in the art to which thistechnology pertains. All publications and patent applications are hereinincorporated by reference to the same extent as if each individualpublication or patent application was specifically and individuallyindicated by reference.

This application is intended to cover adaptations or variations of thepresent subject matter. It is to be understood that the abovedescription is intended to be illustrative, and not restrictive.

1.-20. (canceled)
 21. A vent assembly comprising: a housing defining acavity, a first end, a second end, a vent opening, a valve opening, anda coupling structure towards the second end; a passive airflow ventdisposed in the housing across the vent opening, wherein the housingdefines a housing opening between an ambient environment and the cavityto define a first fluid flow pathway between the ambient environment andthe passive airflow vent; and a one-way relief valve disposed in thehousing and forming a seal over the valve opening, wherein the one-wayrelief valve is arranged in parallel with the passive airflow vent withrespect to airflow through the housing, wherein the passive airflow ventand the one-way relief valve share a central axis, and wherein the valveopening comprises a plurality of openings defining a segmented annulusabout the central axis, and wherein the fluid flow pathway defines atortuous path between the housing opening and the one-way relief valve.22. The vent assembly of claim 21, further comprising an end cap coupledto the housing towards the first end.
 23. The vent assembly of claim 22,wherein the end cap defines the first end of the housing and the end capextends across the one-way relief valve and the passive airflow vent.24. The vent assembly of claim 21, wherein the passive airflow ventcomprises a breathable membrane.
 25. The vent assembly of claim 21, thehousing comprising a first obstruction, wherein the first obstruction ispositioned between the housing opening and the passive airflow vent. 26.The vent assembly of claim 21, the housing comprising a secondobstruction extending into the fluid flow pathway, wherein the secondobstruction is positioned between the housing opening and the one-wayrelief valve.
 27. The vent assembly of claim 21, the coupling structuredefining a fluid flow pathway between an outside of the housing and thepassive airflow vent.
 28. The vent assembly of claim 21, wherein thehousing defines a first fluid flow pathway between an outside of thehousing and the passive airflow vent, the coupling structure defines asecond fluid flow pathway between the outside of the housing and thepassive airflow vent, and the one-way relief valve is configured tounseal when the pressure in the second fluid flow pathway is greaterthan the pressure in the first fluid flow pathway by 0.5 to 1 psi. 29.The vent assembly of claim 21, wherein the housing further defines amounting surface that defines the vent opening.
 30. The vent assembly ofclaim 21, wherein the vent opening is a plurality of openings defining asegmented annulus about the central axis.
 31. The vent assembly of claim21, wherein the one-way relief valve is an umbrella valve.
 32. The ventassembly of claim 21, wherein the housing defines radial openings aboutthe central axis, wherein the radial openings define a fluid flowpathway between an outside of the housing and the passive airflow vent.33. The vent assembly of claim 21, wherein the passive airflow vent andthe one-way relief valve are concentric.
 34. The vent assembly of claim21, further comprising a seal abutting the coupling structure.
 35. Avent assembly comprising: a housing defining a cavity, a first end, asecond end, a vent opening, a valve opening, and a coupling structuretowards the second end; a passive airflow vent disposed in the housingacross the vent opening; and a one-way relief valve disposed in thehousing and forms a seal over the valve opening, wherein the one-wayrelief valve is arranged in parallel with the passive airflow vent withrespect to airflow through the housing, wherein the passive airflow ventand the one-way relief valve share a central axis, and wherein the ventopening is a plurality of openings defining a segmented annulus aboutthe central axis.
 36. The vent assembly of claim 35, wherein the one-wayrelief valve is constructed of an elastomeric material.
 37. The ventassembly of claim 35, wherein the passive airflow vent comprisespolytetrafluoroethylene.
 38. The vent assembly of claim 35, wherein thecoupling structure defines one in the group consisting of a snap-fit anda screw fit that is configured to engage a battery housing.
 39. The ventassembly of claim 35, wherein the housing defines a first fluid flowpathway between an outside of the housing and the passive airflow vent,the coupling structure defines a second fluid flow pathway between theoutside of the housing and the passive airflow vent, and the one-wayrelief valve is configured to unseal when the pressure in the secondfluid flow pathway is greater than the pressure in the first fluid flowpathway by 0.5 to 1 psi.
 40. The vent assembly of claim 35, wherein thevalve opening comprises a plurality of openings defining a segmentedannulus about the central axis.